Wheeled luggage has been popularly used in recent years by travelers in various forms of transportation. When designing a wheeled luggage, a number of important criteria of the luggage must be satisfied. For instance, the luggage should be rigidly constructed for surviving rough handling when pulled in the streets, in and out of buildings with ascending or descending steps, and in and out of various forms of carriers such as airplanes or motor vehicles. The wheeled luggage must also have adequate wheel means such that a luggage can be pulled along on a pavement with relative ease. The wheeled luggage should also have a convenient pull-handle system that can be easily stowed away when not in use and extended when needed.
One difficulty frequently encountered in using a wheeled luggage is the lack of a reliable pull-handle system that can be used for locking or unlocking a handle so that a handle can be retracted for storage or extended for use. The lack of a reliable and easy to use handle locking/unlocking mechanism presents serious problems and great inconveniences in the use of a wheeled luggage. For instance, when a luggage is positioned sideways or in an upside-down position, the gravity of the handle may cause the accidentally extension of the handle and cause problems to a luggage conveyor belt. As a result, serious damages can occur to the luggage or to the conveyor system. Efforts have been made by others to remedy the problems. For instance, in U.S. Pat. No. 5,526,908, a retractable handle assembly which can be easily expanded and folded without exerting a large force thereon. The retractable handle assembly includes a hollow bracket mounted on a top plate of one of the half bodies thereof, a pair of lug portions each formed on one of the distal end portions of the bracket and each having a first bore laterally defined therein, a pair of outer tubes each securely mounted between the lug portion and a bottom plate of the half body and each having a second bore laterally defined therein for aligning with the first bore, the pair of inner tubes each is slidably mounted in one of the outer tubes and each having a third bore laterally defined therein for aligning with the second bore, a substantially U-shaped handle portion mounted on the bracket and having two free end portions each engaged with the upper end of a corresponding one of the inner tubes, a pressing member movably mounted in a hollow bracket and including a knob extending through an opening of the hollow bracket, a biasing member mounted on an underside of the present member and including a pair of stubs each respectively extending through the first bore of associated lug portion, the second bore of associated outer tube and the third bore of associated inner tube.
In another issued U.S. Pat. No. 5,499,426, a handle device is disclosed which includes a pair of storage tubes adapted to be mounted on a rear face of a wheeled suitcase, a seat frame, a handle member and a locking mechanism. The locking mechanism is provided in the receiving space of the seat frame and includes two projecting members, a biasing unit between the projecting members for biasing the projection members toward the storage tubes and for locking the handle member relative to the storage tubes when the two engaging holes are in alignment, and a retracting unit for retracting the projecting members to release the handle member relative to the storage tubes. U.S. Pat. No. 5,431,428 discloses a carrying case assembly that is equipped with a collapsible handle assembly disposed within the case, the handle assembly includes a push button which allows the handle to collapse within the case. The handle assembly further includes a lock means for holding the first handle portion in an extended position relative to the second handle portion, the handle lock means includes a selectably releasable handle-locking protrusions on one of the first and second handle portions, movable in opposing directions toward and away from the other of the first and second handle portions into and out of engagement therewith. In still another issued patent, U.S. Pat. No. 5,502,876 a pull handle for a trunk is disclosed which includes a pair of driving rods each having a wedge member disposed at the bottom end thereof and is in abutment with a spring biased locking seat having an oblique cam surface. Each driving rod is housed in a hollow tube and the locking seat is in selective engagement with one of a plurality of spaced retaining slots disposed on a movable sleeve which accommodates each hollow tube.
A conventional pull-handle assembly that is retractable and extendable is shown in FIG. 1. A pull-handle system 10 is constructed by a U-shaped handle assembly 14 and a pair of parallelly extended support tubes 12. In each of the support tube 12, there is a tubular shaped opening 16 and an aperture 18 for engaging to a locking pin 28. The U-shaped handle assembly 14 includes a handle grip 20 and a pair of sliding tubes 22 affixed to the two opposite ends of the handle grip 20. At the bottom end of the sliding tube 22, a latching device 24 is attached. The latching device 24 is equipped with a locking pin 28 for engaging the aperture 18 provided at or near the upper end of the support tube 12. A push-button 26 is installed in the handle grip 20 through an aperture 25. This is shown in FIG. 2. The push-button 26 is used to control the latching device 24 on the sliding tube 22 for locking or unlocking the sliding tube 22 to the support tube 12.
The sliding tube 22 is inserted into the tubular opening 16 in the support tube 12 at its free end, i.e., opposite to the end that is affixed to the handle grip 20, such that it may slide freely inside the tubular opening 16. At the lower extremity of the sliding tube 22, a latching device 24 is provided which is equipped with a retractable locking pin 28 for engaging with the aperture 18 provided in the support tube 12 such that an extended position of the retractable pull-handle can be secured. At the lower end (not shown) of the support tube 12, another aperture (not shown) is provided for engaging retractable locking pin 28 when the sliding tube 22 is fully inserted into the support tube 12 and thus locking the two tubes in a stowed away position when the pull-handle is not needed. When the push-button 26 is pressed downwardly, the retractable locking pin 28 on the latching device 24 at the tip of the sliding tube 22 is retracted inwardly such that the sliding tube 22 unlocks itself from the support tube 12 to enable the sliding tube 22 to slide freely in the tubular opening 16 ofthe support tube 12.
FIG. 2 shows a cross-sectional view of the pull-handle assembly 14 taken along line 2--2 of FIG. 1. FIG. 2 shows that inside the pull-handle assembly 14, each one of the two sliding tube 22 has a tubular opening 30 therein. Within the handle grip 20, there is provided an interior chamber 32 which is open to the tubular openings 30 in the two sliding tubes 22. The push-button 26 is positioned at the center of the chamber 32. Each of the latching device 24 on the sliding tube 22 is equipped with a latch hook 38 positioned at the top of the latching device 24 and a retractable locking pin 28 positioned on the inside of the latching device 24.
On both sides of the push-button 26, there is provided a cantilevered arm 33 for controlling the latching device 24 at the lower extremity of the two sliding tubes 22. The cantilever arm 33 is fixed at a pivoting point 34 such that the two ends of the cantilever arm 36, 37 may move freely up and down. A rigid control rod 36 is positioned inside the tubular opening 30 of the sliding tube 22 and hooked onto a notch 35 provided at the outer end 36 of the cantilever arm 33. The lower end of the rigid control rod 36 is attached to the latch hook 38 to allow the operation of the locking pin 28 from an extended position to a retracted position when the rod 36 is pulled up by the cantilevered arm 33. The inner end 37 of the cantilever arm 33 is positioned directly under the push-button 26 such that when the push-button 26 is pressed downwardly, the inner end 37 of the cantilever arm 33 is pushed downwardly. The cantilever arm 33 thus pivots at the pivoting point 34 and causing the outer end 36 of the arm 33 to move upward. The rigid control rod 36 is thus pulled up together with the latch hook attached to the latching device 24. The locking pin 28 is retracted as a result from the aperture 18 to free the inner tube 22 from locking to the support tube 12. This allows the free movement of the sliding tube 22 inside the tubular opening 16 of the support tube 12.
Numerous problems in the construction and the operation of the conventional pullhandle system shown in FIGS. 1 and 2 are encountered. The pull-handle system 10 utilizes a cantilever arm 33 and a rigid control rod 36 for achieving the locking/unlocking functions of the inner tube 22 to the support tube 12. Even though the mechanism is relatively simple, the bulky volume of the cantilever arm 33 and the large volume of space it requires when pivoting around the pivoting point 34 making it impossible for a more compact handle grip 20 to be designed. Moreover, since neither the cantilever arm 33 nor the rigid control rod 36 is flexible, the structure cannot be utilized in a non-linear handle grip configuration. For instance, the structure cannot be easily adapted to the modern ergonomically designed handle grips which are normally more curved than a conventional handle grip.
It is therefore an object of the present invention to provide a retractable pull-handle system that does not have the drawbacks or the shortcomings of the conventional pull-handle systems.
It is another object of the present invention to provide a retractable pull-handle system that does not require the use of rigid cantilever arms and control rods for engaging and disengaging a handle locking mechanism.
It is a further object of the present invention to provide a retractable pull-handle system that utilizes a flexible steel cable for operating a locking/unlocking system by the simple operation of a push-button.
It is another further object of the present invention to provide a retractable pull-handle system that can be advantageously used on a wheeled luggage.
It is still another object of the present invention to provide a retractable pull-handle system that utilizes a braided flexible cable for operating a handle locking/unlocking system.
It is yet another object of the present invention to provide a retractable pull-handle system for use on a wheeled luggage for operating the retraction/extension of an inner sliding tube in an outer support tube.
It is yet another further object of the present invention to provide a retractable pull-handle system for use on a wheeled luggage by utilizing a push-button that has a pair of inclined surfaces for engaging a pair of sliding blocks having correspondingly inclined surfaces for operating the locking/unlocking of the pull-handle through a flexible metal cable.